1) Field of the Invention
The present invention relates generally to cultivators, and, more specifically, to shank structure for row crop cultivators or the like.
2) Related Art
Row crop cultivators often include spring trip standards for cultivating in conditions where obstacles are likely to be encountered. For minimum obstruction conditions, a lower cost and lighter weight alternative to the spring trip standards is preferred.
During the initial cultivation, several standards are usually provided between the rows of crop. However, for later high speed lay-by of the crop, the number of standards is typically reduced and sometimes only a single standard is required between each pair of rows. The number of standards may also need to be varied to accommodate cultivation of special crops, such as sugar beets, or to handle skip-row crops. Changeover from one number of standards to a smaller number requires removal of standards or rotation of the standards upwardly. Removal of standards, and the later reattachment of the standards, are time-consuming and inconvenient tasks.
Removal and replacement of the sweeps or maintenance of the sweeps while on the standard is difficult as a result of the sweeps normally being quite low to the ground and the attaching bolts being at an awkward angle. Clearing blockages caused by build-up of residue also presents problems because of the relatively inaccessible position of the shank and sweep. A typical low-cost shank assembly often lacks an acceptable shank attitude adjustment and/or sweep pitch adjustment. Some light-weight assemblies, such as those utilizing S-tine shanks, may in some field conditions provide inadequate support for consistent sweep action. Lateral stability often is severely compromised with low cost and light-weight assemblies.
Flat profile sweeps, used primarily for cultivating cotton and peanut crops so only a small amount of soil is disturbed, are typically connected to the rig with rigid, upright shanks. Such shanks usually have poor residue flow and soil disturbance characteristics.